Fmoc-Ala-Ala-Phe-OH is a preassembled, all-L Fmoc-protected tripeptide fragment corresponding to Fmoc-L-Ala-L-Ala-L-Phe-OH. Using a defined tripeptide building block can reduce the number of sequential coupling/deprotection cycles required to introduce an Ala-Ala-Phe motif and can simplify route development for peptides containing this sequence.

The C-terminal phenylalanine carboxyl group remains available for coupling, while the N-terminal Fmoc group provides standard orthogonal protection for subsequent peptide elongation.

Product Information

Why Use a Preassembled Tripeptide Fragment?

Fragment building blocks can reduce synthesis steps, resin exposure and cumulative deletion-sequence risk when a short motif occurs repeatedly or is difficult to assemble efficiently on resin. They are also useful for convergent synthesis and peptide-library workflows where a defined fragment is treated as a modular unit.

Fragment Coupling Considerations

The C-terminal Phe residue is activated during coupling to the next amine. As with other peptide-fragment condensations, coupling reagent, base, activation time and temperature should be selected with attention to epimerization and incomplete conversion. Fragment purity and stereochemical identity are important procurement parameters.

Applications

Fmoc-Ala-Ala-Phe-OH can be used in Fmoc-SPPS, solution-phase fragment coupling, preparation of peptide libraries, synthesis of Ala-Ala-Phe-containing peptide standards and route development for longer peptide sequences.

Ala-Ala-Phe motifs also occur in some protease-substrate designs, but this protected tripeptide building block is not itself a fluorogenic or chromogenic enzyme substrate. Assay activity depends on the complete labeled/substituted peptide substrate.

Downstream Assay Relevance

After incorporation into a final peptide and appropriate purification, Ala-Ala-Phe-containing constructs may be evaluated in protease, binding, stability or cellular assays according to the final sequence and reporter architecture.

Product Documents

A Material Safety Data Sheet (MSDS) is available for this product to support laboratory handling, storage and safety assessment.

MSDS_Fmoc-Ala-Ala-Phe-OH_AS4059

Certificates of Analysis (COAs) are batch-specific. Please contact us to request the COA for your product, and we will provide it by email.

Frequently Asked Questions

Is Fmoc-Ala-Ala-Phe-OH a single amino acid?

No. It is a preassembled Fmoc-protected tripeptide fragment containing L-Ala-L-Ala-L-Phe.

Why use a tripeptide fragment instead of three separate amino acids?

A defined fragment can reduce the number of synthetic cycles and may simplify route development, especially when the motif is repeatedly used.

Is this product a protease substrate?

No. It is a synthesis building block. Protease substrates require an appropriately designed complete peptide, often including reporter or leaving groups.

Related Technical Resources

Explore Specialty Peptide Building Blocks and Custom Peptide Synthesis.

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